验证一个ASP.NET应用程序和页面的生命周期的实现代码

时间:2021-10-26 15:58:48

如果我们能更好地掌握这样一个过程,那么对单个ASP.NET Page的生命周期也能更好地了解: 
下面介绍如何编写一个简单的ASP.NET 页面和一个简单的HttpModule,对MSDN里提到的ASP.NET的生命周期进行验证 
1. 首先使用Visual Studio 2010建立一个空的ASP.NET网站 (ASP.NET 4.0) 
2. 添加一个Default.aspx,添加三个ASP.NET控件,分别为TextBox,Button和Validator: 

复制代码代码如下:

   
<form id="form1" runat="server"> 
<div> 
<asp:TextBox ID="txtName" runat="server"></asp:TextBox> 
<asp:Button ID="btnSubmit" runat="server" Text="OK" onclick="btnSubmit_Click" /> 
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ErrorMessage="Please input your name!" ControlToValidate="txtName" ForeColor="#FF3300"> 
</asp:RequiredFieldValidator> 
</div> 
</form> 


3. 添加一个ASP.NEt的App_code文件夹,新建一个类,内容为: 

复制代码代码如下:


using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
public class TestClass : IHttpModule 

HttpApplication httpApp; 
public static List<string> EventList = new List<string>(); 
public TestClass() 


public void Dispose() 
{ } 
public void Init(HttpApplication context) 

this.httpApp = context; 
//EventList.Clear(); 
EventList.Add("Initiated"); 
context.BeginRequest += new EventHandler(context_BeginRequest); 
context.AuthenticateRequest += new EventHandler(context_AuthenticateRequest); 
context.AuthorizeRequest += new EventHandler(context_AuthorizeRequest); 
context.ResolveRequestCache += new EventHandler(context_ResolveRequestCache); 
context.AcquireRequestState += new EventHandler(context_AcquireRequestState); 
context.PreRequestHandlerExecute += new EventHandler(context_PreRequestHandlerExecute); 
context.PostReleaseRequestState += new EventHandler(context_PostReleaseRequestState); 
context.ReleaseRequestState += new EventHandler(context_ReleaseRequestState); 
context.UpdateRequestCache += new EventHandler(context_UpdateRequestCache); 
context.EndRequest += new EventHandler(context_EndRequest); 

private void context_EndRequest(object sender, EventArgs e) 

EventList.Add("HTTP Modules: End Request <hr>"); 
foreach (string str in EventList) 

httpApp.Response.Write(str + "<br>"); 

EventList.Clear(); 

void context_UpdateRequestCache(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Update Request Cache"); 

void context_ReleaseRequestState(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Release Request State"); 

void context_PostReleaseRequestState(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Post Release Request State"); 

void context_PreRequestHandlerExecute(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Pre Request Handler Execution"); 

void context_AcquireRequestState(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Acquire Request State"); 

void context_ResolveRequestCache(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Resolve Request"); 

void context_AuthorizeRequest(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Authorize Request"); 

void context_AuthenticateRequest(object sender, EventArgs e) 

EventList.Add("HTTP Modules: AuthenticateRequest"); 

void context_BeginRequest(object sender, EventArgs e) 

EventList.Add("HTTP Modules: Begin Request"); 


4. 修改刚才的Default.aspx的后台cs代码: 

复制代码代码如下:


using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.UI; 
using System.Web.UI.WebControls; 
public partial class _Default : System.Web.UI.Page 

protected void Page_Init() 

TestClass.EventList.Add("ASP.NET Page: Page_Init"); 

protected void Page_Load(object sender, EventArgs e) 

TestClass.EventList.Add("ASP.NET Page: Page_Load"); 

public override void Validate() 

TestClass.EventList.Add("ASP.NET Page: Validated"); 
base.Validate(); 

protected void btnSubmit_Click(object sender, EventArgs e) 

TestClass.EventList.Add("ASP.NET Page: Event"); 

protected override void Render(HtmlTextWriter writer) 

TestClass.EventList.Add("ASP.NET Page: Render"); 
base.Render(writer); 

protected void Page_Unload(object sender, EventArgs e) 

TestClass.EventList.Add("ASP.NET Page: Unload"); 


5. 修改web.config内容如下: 

复制代码代码如下:


<configuration> 
<system.web> 
<compilation debug="true" targetFramework="4.0"/> 
</system.web> 
<system.web> 
<httpModules> 
<add name="TestClass" type="TestClass"/> 
</httpModules> 
</system.web> 
</configuration> 


6. Ctrl+F5执行,在浏览器里可以看到:
验证一个ASP.NET应用程序和页面的生命周期的实现代码

7. 在文本框内输入内容,可得:

 验证一个ASP.NET应用程序和页面的生命周期的实现代码
结论: 
1. Module只初始化了一次,当页面postback的时候,module不会再初始化。 
2. Validate和Event事件在页面第一次初始化的时候不会触发,但是由于页面本身存在validate控件和事件按钮,所以这两个事件在第二次会被触发。 
本文参考了codeproject.com的如下一篇文章http://www.codeproject.com/KB/aspnet/ASPDOTNETPageLifecycle.aspx